need help!

How does a two-transistors LED flasher (flip-flop) circuit work?

I don't know when does a capacitors and the transistors switch and turn the other off considering the voltage across them.........well, on other words, don't know what makes the LEDs do the flipflop thing......HELP

It is called a Transistor Multivibrator.
there are tutorials about how it works on the internet. Use Google to find one.

Be careful. The first link in Google for me has the capacitors connected with their polarity backwards.